39
39

May 11, 2019
05/19

May 11, 2019
by
Jeremy Berg, Illinois State University

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Abstract In November 2005, access to all recordings of Grateful Dead shows on the Internet Live Music Archive was abruptly discontinued. Over the next nine days, the band, their fans, and the Archive argued the matter on a nationwide stage, before a compromise on access was reached. The controversy touched on issues of copyright, ownership, and the effects of the Internet on making fan projects more widespread and organized than ever before. This case study traces the history of the controversy...

Topics: internet archive, grateful dead

2,114
2.1K

Nov 10, 2016
11/16

Nov 10, 2016
by
Stephen Mason

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Stephen Mason is a leading authority on electronic signatures and electronic evidence, having advised global corporations and governments on these topics. He is also the founder and editor of the international open source journal the Digital Evidence and Electronic Signature Law Review . Stephen is an Associate Research Fellow at the IALS. This fourth edition of the well-established practitioner text sets out what constitutes an electronic signature; the form an electronic signature can take;...

Topic: electronic signature

782
782

Feb 6, 2014
02/14

Feb 6, 2014
by
Ekhtiar, Maryam D. and Claire Moore, ed.

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985
985

Nov 14, 2013
11/13

Nov 14, 2013
by
Peter M. Neumann

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These notes are intended as a rough guide to the eight-lecture course Introduction to Pure Mathematics which is a part of the Oxford 1st-year undergraduate course for the Preliminary Examination in Mathematics. Please do not expect a polished account. They are my personal lecture notes, not a carefully checked textbook. Nevertheless, I hope they may be of some help.

Topic: Maths

Source: http://www.flooved.com/reader/1056

2,120
2.1K

Nov 14, 2013
11/13

Nov 14, 2013
by
Prof. Jim Hefferon

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on functions involving a single independent variable and a single dependent variable. For

Topics: Maths, Mathematics

Source: http://www.flooved.com/reader/3490

2,559
2.6K

Nov 14, 2013
11/13

Nov 14, 2013
by
William F. Trench

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The book is designed to �ll the gaps left in the development of calculus as it is usually presented in an elementary course, and to provide the background required for insight into more advanced courses in pure and applied mathematics.

Topics: Real Numbers, Analysis, Mathematics

Source: http://www.flooved.com/reader/3549

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426

Nov 14, 2013
11/13

Nov 14, 2013
by
Prof. P.D. Magnus

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forall x is an open access introductory textbook in formal logic. It covers translation, proofs, and formal semantics for sentential and predicate logic.

Topics: Maths, Mathematics

Source: http://www.flooved.com/reader/3495

690
690

Nov 14, 2013
11/13

Nov 14, 2013
by
Prof. Martin V. Day

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simultaneously.

Topics: Maths, Mathematics

Source: http://www.flooved.com/reader/3478

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1.2K

Nov 14, 2013
11/13

Nov 14, 2013
by
Prof. Joseph Fields

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f(x). However, many of the functions of importance both within mathematics itself as

Topics: Maths, Mathematics

Source: http://www.flooved.com/reader/3477

491
491

Nov 14, 2013
11/13

Nov 14, 2013
by
Susan Dean;Barbara Illowsky

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Abstract: This module provides examples of Hypothesis Testing of a Single Mean and a Single Proportion as a part of the Collaborative Statistics collection (col10522) by Barbara Illowsky and Susan Dean.

Topics: Maths, Statistics and Probability, Statistics, Hypothesis Testing, Mathematics

Source: http://www.flooved.com/reader/1565

167
167

Nov 14, 2013
11/13

Nov 14, 2013
by
Zdzislaw (Gustav) Meglicki

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We introduce homogeneous Markov processes and show how the apparatus developed so far simplifies for this class. This module does not discuss more specific Markov processes--continuous, jump, birth-death, etc.

Topics: Maths, Stochastic Analysis, Stochastic Processes, Markov Processes, Mathematics

Source: http://www.flooved.com/reader/1591

21,639
22K

Nov 14, 2013
11/13

Nov 14, 2013
by
David Lippman;Jeff Eldridge;Mike Kenyon;Lawrence Morales;Melonie Rasmussen

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Topics: Maths, Mathematics

Source: http://www.flooved.com/reader/3501

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94

Nov 14, 2013
11/13

Nov 14, 2013
by
Zdzislaw (Gustav) Meglicki

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In this module we are also going to take another look at quantum mechanics, asking if quantum mechanics can be simulated by jump Markov processes. There was a vigorous discussion about this in the literature.

Topics: Maths, Mathematics

Source: http://www.flooved.com/reader/1660

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1.7K

Nov 14, 2013
11/13

Nov 14, 2013
by
Reinhard Diestel

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This is the electronic �professional edition� of the Springer book "Graph Theory", from their series Graduate Texts in Mathematics, vol. 173.... this book o_ers an introduction to the theory of graphs as part of (pure) mathematics; it contains neither explicit algorithms nor �real world� applications. My hope is that the potential for depth gained by this restriction in scope will serve students of computer science as much as their peers in mathematics...

Topics: Maths, Graph Theory, Basics, Connectivity and Matchings, Extremal Graph Theory, Eigenvalue Methods,...

Source: http://www.flooved.com/reader/3447

298
298

Nov 14, 2013
11/13

Nov 14, 2013
by
Z. Qian

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Topics: Maths, Mathematics

Source: http://www.flooved.com/reader/1094

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541

Nov 14, 2013
11/13

Nov 14, 2013
by
Peter Ouwehand

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Topic: Maths

Source: http://www.flooved.com/reader/3386

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3.2K

Nov 14, 2013
11/13

Nov 14, 2013
by
Barbara Illowsky;Susan Dean

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The textbook was developed over several years and has been used in regular and honors-level classroom settings and in distance learning classes. This textbook is intended for introductory statistics courses being taken by students at two� and four�year colleges who are majoring in fields other than math or engineering. Intermediate algebra is the only prerequisite. The book focuses on applications of statistical knowledge rather than the theory behind it.

Topics: Maths, Mathematics

Source: http://www.flooved.com/reader/3483

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1.5K

Nov 14, 2013
11/13

Nov 14, 2013
by
Prof. John Erdman

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The current set of notes is an activity-oriented companion to the study of real analysis. It is intended as a pedagogical companion for the beginner, an introduction to some of the main ideas in real analysis, a compendium of problems I think are useful in learning the subject, and an annotated reading/reference list

Topics: Maths, Mathematics

Source: http://www.flooved.com/reader/3485

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197

Nov 14, 2013
11/13

Nov 14, 2013
by
Christina Goldschmidt

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These notes are intended to complement the contents of the lectures. They contain more material than the lectures and, in particular, a few more examples. You are nonetheless strongly encouraged to attend all of the lectures. An original version of the �rst part of these notes was written by Alison Etheridge and I have also made extensive use of notes by Neil Laws and Jonathan Marchini.

Topics: Maths, Mathematics

Source: http://www.flooved.com/reader/1092

577
577

Nov 14, 2013
11/13

Nov 14, 2013
by
G.'t Hooft;S. Vandoren

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Prologue General relativity is a beautiful scheme for describing the gravitational �eld and the equations it obeys. Nowadays this theory is often used as a prototype for other, more intricate constructions to describe forces between elementary particles or other branches of fundamental physics. This is why in an introduction to general relativity it is of importance to separate as clearly as possible the various ingredients that together give shape to this paradigm. After explaining the...

Topic: Maths

Source: http://www.flooved.com/reader/2932

1,564
1.6K

Nov 14, 2013
11/13

Nov 14, 2013
by
Peter Ouwehand

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These notes are for a short course in set theory at the undergraduate level at Stellenbosch University. No pretense at orignality is claimed. Though ampli�ed by material from a number of additional sources, the debt to the �rst few chapters of the book Set Theory, by Thomas Jech, Springer 2003, should be easily discernible.

Topics: Maths, Logic, Numbers and Set Theory, Set Theory, Mathematics

Source: http://www.flooved.com/reader/3368

166
166

Jul 20, 2013
07/13

Jul 20, 2013
by
Dierk Schleicher

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We describe an interesting interplay between symbolic dynamics, the structure of the Mandelbrot set, permutations of periodic points achieved by analytic continuation, and Galois groups of certain polynomials. Internal addresses are a convenient and efficient way of describing the combinatorial structure of the Mandelbrot set, and of giving geometric meaning to the ubiquitous kneading sequences in human-readable form (Sections 3 and 4). A simple extension, \emph{angled internal addresses},...

Source: http://arxiv.org/abs/math/9411238v3

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47

Jul 20, 2013
07/13

Jul 20, 2013
by
Pierre-Olivier Amblard; Jean-François Coeurjolly; Frédéric Lavancier; Anne Philippe

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This paper reviews and extends some recent results on the multivariate fractional Brownian motion (mfBm) and its increment process. A characterization of the mfBm through its covariance function is obtained. Similarly, the correlation and spectral analyses of the increments are investigated. On the other hand we show that (almost) all mfBm's may be reached as the limit of partial sums of (super)linear processes. Finally, an algorithm to perfectly simulate the mfBm is presented and illustrated...

Source: http://arxiv.org/abs/1007.0828v2

121
121

Jul 20, 2013
07/13

Jul 20, 2013
by
Hoeskuldur P. Halldorsson

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We give a classification of all self-similar solutions to the curve shortening flow in the plane.

Source: http://arxiv.org/abs/1007.1617v2

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43

Jul 20, 2013
07/13

Jul 20, 2013
by
Sebastian Casalaina-Martin; Radu Laza

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A key tool in the study of algebraic surfaces and their moduli is Brieskorn's simultaneous resolution for families of algebraic surfaces with simple (du Val or ADE) singularities. In this paper we show that a similar statement holds for families of curves with at worst simple (ADE) singularities. For a family $\mathscr X\to B$ of ADE curves, we give an explicit and natural resolution of the rational map $B\to \bar M_g$. Moreover, we discuss a lifting of this map to the moduli stack $ \bar...

Source: http://arxiv.org/abs/1007.0265v2

108
108

Jul 20, 2013
07/13

Jul 20, 2013
by
Ery Arias-Castro; Emmanuel J. Candès; Yaniv Plan

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Testing for the significance of a subset of regression coefficients in a linear model, a staple of statistical analysis, goes back at least to the work of Fisher who introduced the analysis of variance (ANOVA). We study this problem under the assumption that the coefficient vector is sparse, a common situation in modern high-dimensional settings. Suppose we have $p$ covariates and that under the alternative, the response only depends upon the order of $p^{1-\alpha}$ of those, $0\le\alpha\le1$....

Source: http://arxiv.org/abs/1007.1434v2

50
50

Jul 20, 2013
07/13

Jul 20, 2013
by
Marco Bardoscia; Roberto Bellotti

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A novel dynamical model for the study of operational risk in banks and suitable for the calculation of the Value at Risk (VaR) is proposed. The equation of motion takes into account the interactions among different bank's processes, the spontaneous generation of losses via a noise term and the efforts made by the bank to avoid their occurrence. Since the model is very general, it can be tailored on the internal organizational structure of a specific bank by estimating some of its parameters...

Source: http://arxiv.org/abs/1007.0026v6

106
106

Jul 20, 2013
07/13

Jul 20, 2013
by
Brian Skinner; B. I. Shklovskii

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In electronic devices where a two-dimensional electron gas (2DEG) comprises one or both sides of a plane capacitor, the resulting capacitance $C$ can be larger than the "geometric capacitance" $C_g$ determined by the physical separation $d$ between electrodes. This larger capacitance is known to result from the Coulomb correlations between individual electrons within the low density 2DEG, which lead to a negative thermodynamic density of states (negative compressibility). Experiments...

Source: http://arxiv.org/abs/1007.5308v3

98
98

Jul 20, 2013
07/13

Jul 20, 2013
by
Xavier Bekaert; Nicolas Boulanger; Per Sundell

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Aiming at non-experts, we explain the key mechanisms of higher-spin extensions of ordinary gravity. We first overview various no-go theorems for low-energy scattering of massless particles in flat spacetime. In doing so we dress a dictionary between the S-matrix and the Lagrangian approaches, exhibiting their relative advantages and weaknesses, after which we high-light potential loop-holes for non-trivial massless dynamics. We then review positive yes-go results for non-abelian cubic...

Source: http://arxiv.org/abs/1007.0435v3

85
85

Jul 20, 2013
07/13

Jul 20, 2013
by
V. Gogokhia; M. Vasúth

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The effective potential approach for composite operators is generalized to non-zero temperature in order to derive the non-perturbative analytical equation of state for pure SU(3) Yang-Mills fields valid in the whole temperature range. Adjusting our parametrization of the gluon plasma pressure to the lattice pressure at high temperature for SU(3) Yang-Mills case, we have reproduced well our analytical curves and numbers not only for the pressure but for all other independent thermodynamic...

Source: http://arxiv.org/abs/1007.1573v2

99
99

Jul 20, 2013
07/13

Jul 20, 2013
by
Lutz Warnke

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The K_4-free process starts with the empty graph on n vertices and at each step adds a new edge chosen uniformly at random from all remaining edges that do not complete a copy of K_4. Let G be the random maximal K_4-free graph obtained at the end of the process. We show that for some positive constant C, with high probability as $n \to \infty$, the maximum degree in G is at most $C n^{3/5}\sqrt[5]{\log n}$. This resolves a conjecture of Bohman and Keevash for the K_4-free process and improves...

Source: http://arxiv.org/abs/1007.3037v3

156
156

Jul 20, 2013
07/13

Jul 20, 2013
by
P. J. Bickel; B. J. K. Kleijn

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In a smooth semiparametric estimation problem, the marginal posterior for the parameter of interest is expected to be asymptotically normal and satisfy frequentist criteria of optimality if the model is endowed with a suitable prior. It is shown that, under certain straightforward and interpretable conditions, the assertion of Le Cam's acclaimed, but strictly parametric, Bernstein-von Mises theorem [Univ. California Publ. Statist. 1 (1953) 277-329] holds in the semiparametric situation as well....

Source: http://arxiv.org/abs/1007.0179v3

149
149

Jul 20, 2013
07/13

Jul 20, 2013
by
Akaki Tikaradze

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In this paper we discuss an analogue of the Kac-Weisfeiler conjecture for a certain class of almost commutative algebras. In particular, we prove the Kac-Weisfeiler type statement for rational Cherednik algebras.

Source: http://arxiv.org/abs/1007.2387v4

128
128

Jul 20, 2013
07/13

Jul 20, 2013
by
Eviatar B. Procaccia; Eric Shellef

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Let a simple random walk run inside a torus of dimension three or higher for a number of steps which is a constant proportion of the volume. We examine geometric properties of the range, the random subgraph induced by the set of vertices visited by the walk. Distance and mixing bounds for the typical range are proven that are a $k$-iterated log factor from those on the full torus for arbitrary $k$. The proof uses hierarchical renormalization and techniques that can possibly be applied to other...

Source: http://arxiv.org/abs/1007.1401v3

90
90

Jul 20, 2013
07/13

Jul 20, 2013
by
Josep Diaz; Alberto Marchetti-Spaccamela; Dieter Mitsche; Paolo Santi; Julinda Stefa

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Several social-aware forwarding strategies have been recently introduced in opportunistic networks, and proved effective in considerably in- creasing routing performance through extensive simulation studies based on real-world data. However, this performance improvement comes at the expense of storing a considerable amount of state information (e.g, history of past encounters) at the nodes. Hence, whether the benefits on routing performance comes directly from the social-aware forwarding...

Source: http://arxiv.org/abs/1007.5240v2

55
55

Jul 20, 2013
07/13

Jul 20, 2013
by
Stanislav Volgushev; Holger Dette

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We consider the problem of nonparametric quantile regression for twice censored data. Two new estimates are presented, which are constructed by applying concepts of monotone rearrangements to estimates of the conditional distribution function. The proposed methods avoid the problem of crossing quantile curves. Weak uniform consistency and weak convergence is established for both estimates and their finite sample properties are investigated by means of a simulation study. As a by-product, we...

Source: http://arxiv.org/abs/1007.3376v2

31
31

Jul 20, 2013
07/13

Jul 20, 2013
by
Yajun Zhou

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We study the distribution of eigenvalues for the Green operator occurring in the scattering of electromagnetic waves by an arbitrarily shaped dielectric medium. It is revealed that the totality of eigenvalues (counting multiplicities) can be enumerated as a sequence $ \{\lambda_s\}_{s=1}^N,N\leq\aleph_0$, with only two possible accumulation points $ \{0,-1/2\}$, and the following spectral series converges: $ \sum_{s=1}^N|\lambda_s|^2|1+2\lambda_s|^4

Source: http://arxiv.org/abs/1007.4375v2

54
54

Jul 20, 2013
07/13

Jul 20, 2013
by
Jihoon Park; Przemysław Pawełczak; Pål Grønsund; Danijela Čabrić

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We present an analytical model that enables throughput evaluation of Opportunistic Spectrum Orthogonal Frequency Division Multiple Access (OS-OFDMA) networks. The core feature of the model, based on a discrete time Markov chain, is the consideration of different channel and subchannel allocation strategies under different Primary and Secondary user types, traffic and priority levels. The analytical model also assesses the impact of different spectrum sensing strategies on the throughput of...

Source: http://arxiv.org/abs/1007.5080v3

98
98

Jul 20, 2013
07/13

Jul 20, 2013
by
Georgi S. Medvedev

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A unified approach to studying convergence and stochastic stability of continuous time consensus protocols (CPs) is presented in this work. Our method applies to networks with directed information flow; both cooperative and noncooperative interactions; networks under weak stochastic forcing; and those whose topology and strength of connections may vary in time. The graph theoretic interpretation of the analytical results is emphasized. We show how the spectral properties, such as algebraic...

Source: http://arxiv.org/abs/1007.1234v3

52
52

Jul 20, 2013
07/13

Jul 20, 2013
by
Olivier Bernardi

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Consider a walk in the plane made of $n$ unit steps, with directions chosen independently and uniformly at random at each step. Rayleigh's theorem asserts that the probability for such a walk to end at a distance less than 1 from its starting point is $1/(n+1)$. We give an elementary proof of this result. We also prove the following generalization valid for any probability distribution $\mu$ on the positive real numbers: if two walkers start at the same point and make respectively $m$ and $n$...

Source: http://arxiv.org/abs/1007.4870v3

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35

Jul 20, 2013
07/13

Jul 20, 2013
by
Silvere Bonnabel; Anne Collard; Rodolphe Sepulchre

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The generalization of the geometric mean of positive scalars to positive definite matrices has attracted considerable attention since the seminal work of Ando. The paper generalizes this framework of matrix means by proposing the definition of a rank-preserving mean for two or an arbitrary number of positive semi-definite matrices of fixed rank. The proposed mean is shown to be geometric in that it satisfies all the expected properties of a rank-preserving geometric mean. The work is motivated...

Source: http://arxiv.org/abs/1007.5494v3

44
44

Jul 20, 2013
07/13

Jul 20, 2013
by
Marcin Bienkowski

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In the online packet buffering problem (also known as the unweighted FIFO variant of buffer management), we focus on a single network packet switching device with several input ports and one output port. This device forwards unit-size, unit-value packets from input ports to the output port. Buffers attached to input ports may accumulate incoming packets for later transmission; if they cannot accommodate all incoming packets, their excess is lost. A packet buffering algorithm has to choose from...

Source: http://arxiv.org/abs/1007.1535v3

97
97

Jul 20, 2013
07/13

Jul 20, 2013
by
Elias Gabriel Minian

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We introduce a version of discrete Morse theory for posets. This theory studies the topology of the order complexes K(X) of h-regular posets X from the critical points of admissible matchings on X. Our approach is related to R. Forman's discrete Morse theory for CW-complexes and generalizes Forman and Chari's results on the face posets of regular CW-complexes. We also introduce a homological variant of the theory that can be used to study the topology of triangulable homology manifolds by means...

Source: http://arxiv.org/abs/1007.1930v2

48
48

Jul 20, 2013
07/13

Jul 20, 2013
by
Sergey Rybakov

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Let $A$ be an abelian surface over a finite field $k$. The $k$-isogeny class of $A$ is uniquely determined by a Weil polynomial $f_A$ of degree 4. We give a classification of the groups of $k$-rational points on varieties from this class in terms of $f_A$.

Source: http://arxiv.org/abs/1007.0115v2

107
107

Jul 20, 2013
07/13

Jul 20, 2013
by
Alberto Enciso; Daniel Peralta-Salas

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Motivated by a question of Rubel, we consider the problem of characterizing which noncompact hypersurfaces in $\RR^n$ can be regular level sets of a harmonic function modulo a $C^\infty$ diffeomorphism, as well as certain generalizations to other PDEs. We prove a versatile sufficient condition that shows, in particular, that any (possibly disconnected) algebraic noncompact hypersurface can be transformed onto a union of components of the zero set of a harmonic function via a diffeomorphism of...

Source: http://arxiv.org/abs/1007.5181v3

51
51

Jul 20, 2013
07/13

Jul 20, 2013
by
Marcel Oliver; Claudia Wulff

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We consider semilinear evolution equations for which the linear part generates a strongly continuous semigroup and the nonlinear part is sufficiently smooth on a scale of Hilbert spaces. In this setting, we prove the existence of solutions which are temporally smooth in the norm of the lowest rung of the scale for an open set of initial data on the highest rung of the scale. Under the same assumptions, we prove that a class of implicit, $A$-stable Runge--Kutta semidiscretizations in time of...

Source: http://arxiv.org/abs/1007.4703v3

131
131

Jul 20, 2013
07/13

Jul 20, 2013
by
Delio Mugnolo; Robin Nittka; Olaf Post

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Convergence of operators acting on a given Hilbert space is an old and well studied topic in operator theory. The idea of introducing a related notion for operators acting on arying spaces is natural. However, it seems that the first results in this direction have been obtained only recently, to the best of our knowledge. Here we consider sectorial operators on scales of Hilbert spaces. We define a notion of convergence that generalises convergence of the resolvents in operator norm to the case...

Source: http://arxiv.org/abs/1007.3932v2

70
70

Jul 20, 2013
07/13

Jul 20, 2013
by
Constantinos Kardaras

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In this paper, a study of random times on filtered probability spaces is undertaken. The main message is that, as long as distributional properties of optional processes up to the random time are involved, there is no loss of generality in assuming that the random time is actually a randomized stopping time. This perspective has advantages in both the theoretical and practical study of optional processes up to random times. Applications are given to the stochastic behavior of processes up to...

Source: http://arxiv.org/abs/1007.1124v3

57
57

Jul 20, 2013
07/13

Jul 20, 2013
by
D. Witthaut; M. D. Lukin; A. S. Sørensen

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We discuss a new method for realizing number-resolving and non-demolition photo detectors by strong coupling of light to individual single photon emitters, which act as strong optical non-linearities. As a specific application we show how these elements can be integrated into an error-proof Bell state analyzer, whose efficiency exceeds the best possible performance with linear optics even for a modest atom-field coupling. The methods are error-proof in the sense that every detection event...

Source: http://arxiv.org/abs/1007.3273v2

86
86

Jul 20, 2013
07/13

Jul 20, 2013
by
Andre LeClair

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A new analytic treatment of the two-dimensional Hubbard model at finite temperature and chemical potential is presented. A next nearest neighbor hopping term of strength t' is included. This analysis is based upon a formulation of the statistical mechanics of particles in terms of the S-matrix. In the 2-body scattering approximation, the S-matrix allows a systematic expansion in t/U. We show that for U/t large enough, a region of attractive interactions exists near the Fermi surface due to...

Source: http://arxiv.org/abs/1007.1195v2

106
106

Jul 20, 2013
07/13

Jul 20, 2013
by
Kamal Jain; Vijay Vazirani

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The problem of arriving at a principled method of pricing goods and services was very satisfactorily solved for conventional goods; however, this solution is not applicable to digital goods. This paper studies pricing of a special class of digital goods, which we call {\em semantically substitutable digital goods}. After taking into consideration idiosyncrasies of goods in this class, we define a market model for it, together with a notion of equilibrium. We prove existence of equilibrium...

Source: http://arxiv.org/abs/1007.4586v4

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Jul 20, 2013
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Jul 20, 2013
by
Francesco Mainardi

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The article provides an historical survey of the early contributions on the applications of fractional calculus in linear viscoelasticty. The period under examination covers four decades, since 1930's up to 1970's and authors are from both Western and Eastern countries. References to more recent contributions may be found in the bibliography of the author's book. This paper reproduces, with Publisher's permission, Section 3.5 of the book: F. Mainardi, Fractional Calculus and Waves in Linear...

Source: http://arxiv.org/abs/1007.2959v2

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Jul 20, 2013
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Jul 20, 2013
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Keita Kobayashi; Yoshiya Yamanaka

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We present an extension of Nelson's stochastic quantum mechanics to finite temperature. Utilizing the formulation of Thermo Field Dynamics (TFD), we can show that Ito's stochastic equations for tilde and non-tilde particle positions reproduce the TFD-type Schr\"odinger equation which is equivalent to the Liouville-von Neumann equation. In our formalism, the drift terms in the Ito's stochastic equation have the temperature dependence and the thermal fluctuation is induced through the...

Source: http://arxiv.org/abs/1007.3603v2

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Jul 20, 2013
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Jul 20, 2013
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Tomas Brazdil; Stefan Kiefer; Antonin Kucera; Ivana Hutarova Varekova

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We study termination time and recurrence time in programs with unbounded recursion, which are either randomized or operate on some statistically quantified inputs. As the underlying formal model for such programs we use probabilistic pushdown automata (pPDA) which are equivalent to probabilistic recursive state machines. We obtain tail bounds for the distribution of termination time for pPDA. We also study the recurrence time for probabilistic recursive programs that are not supposed to...

Source: http://arxiv.org/abs/1007.1710v2

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Jul 20, 2013
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Jul 20, 2013
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Roman Kompaneets; Alexei V. Ivlev; Sergey V. Vladimirov; Gregor E. Morfill

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The fundamental higher-order Landau plasma modes are known to be generally heavily damped. We show that these modes for the ion component in a weakly ionized plasma can be substantially modified by ion-neutral collisions and a dc electric field driving ion flow so that some of them can become unstable. This instability is expected to naturally occur in presheaths of gas discharges at sufficiently small pressures and thus affect sheaths and discharge structures.

Source: http://arxiv.org/abs/1007.0142v3

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Jul 20, 2013
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Jul 20, 2013
by
Ivan Donkin; Arthur Hebecker

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We investigate the impact of extra vector-like GUT multiplets on the predicted value of the strong coupling. We find in particular that Yukawa couplings between such extra multiplets and the MSSM Higgs doublets can resolve the familiar two-loop discrepancy between the SUSY GUT prediction and the measured value of alpha_3. Our analysis highlights the advantages of the holomorphic scheme, where the perturbative running of gauge couplings is saturated at one loop and further corrections are...

Source: http://arxiv.org/abs/1007.3990v6

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Jul 20, 2013
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Jul 20, 2013
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Andreas Seeger; James Wright

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We prove three results concerning convolution operators and lacunary maximal functions associated to dilates of measures. First, we obtain an $H^1$ to $L^{1,\infty}$ bound for lacunary maximal operators under a dimensional assumption on the underlying measure and an assumption on an $L^p$ regularity bound for some $p>1$. Secondly, we obtain a necessary and sufficient condition for $L^2$ boundedness of lacunary maximal operator associated to averages over convex curves in the plane. Finally...

Source: http://arxiv.org/abs/1007.4731v2

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Jul 20, 2013
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Jul 20, 2013
by
Mario Maican

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We find locally free resolutions of length one for all semi-stable sheaves supported on curves of multiplicity five in the complex projective plane. In some cases we also find geometric descriptions of these sheaves by means of extensions. We give natural stratifications for their moduli spaces and we describe the strata as certain quotients modulo linear algebraic groups. In most cases we give concrete descriptions of these quotients as fibre bundles.

Source: http://arxiv.org/abs/1007.1815v3

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Jul 20, 2013
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Jul 20, 2013
by
Vladan Pankovic; Darko V. Kapor

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In this work we apply Bohr-Sommerfeld (Old quantum atomic) theory for analysis of some remarkable electro-dynamical problems, concretely magnetic monopoles, electron electromagnetic mass and fine structure constant. We reproduce exactly some basic elements of the Dirac magnetic monopoles theory, especially Dirac electric/magnetic charge quantization condition. It follows after application of Bohr-Sommerfeld theory at the system, simply called magnetic monopole "atom", consisting of...

Source: http://arxiv.org/abs/1007.0340v5

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Jul 20, 2013
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Jul 20, 2013
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Philip F. Hopkins; Eliot Quataert

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We present analytic calculations of angular momentum transport and gas inflow in galaxies, from scales of ~kpc to deep in the potential of a central black hole (BH). We compare these analytic calculations to numerical simulations and use them to develop a sub-grid model of BH growth that can be incorporated into semi-analytic models or cosmological simulations. Both analytic calculations and simulations argue that the strongest torque on gas arises when non-axisymmetric perturbations to the...

Source: http://arxiv.org/abs/1007.2647v2

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Jul 20, 2013
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Jul 20, 2013
by
Ion I. Cotaescu; Cosmin Crucean

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We construct the de Sitter QED in Coulomb gauge assuming that the quantum modes are prepared by a global apparatus which is able to determine a stable and invariant vacuum state, independent on the local coordinates. Then we proceed in traditional manner postulating the appropriate equal-time commutators and anti-commutators of the interacting fields and deriving the perturbation expansion of the scattering operator. In this approach the $in -out$ transitions amplitudes, measured by the same...

Source: http://arxiv.org/abs/1007.4647v4

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Jul 20, 2013
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Jul 20, 2013
by
Jaroslaw Byrka; MohammadReza Ghodsi; Aravind Srinivasan

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We study LP-rounding approximation algorithms for metric uncapacitated facility-location problems. We first give a new analysis for the algorithm of Chudak and Shmoys, which differs from the analysis of Byrka and Aardal in that now we do not need any bound based on the solution to the dual LP program. Besides obtaining the optimal bifactor approximation as do Byrka and Aardal, we can now also show that the algorithm with scaling parameter equaling 1.58 is, in fact, an 1.58-approximation...

Source: http://arxiv.org/abs/1007.3611v2

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Jul 20, 2013
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Jul 20, 2013
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Robert Thijs Kozma; Jenő Szirmai

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The goal of this paper to determine the optimal horoball packing arrangements and their densities for all four fully asymptotic Coxeter tilings (Coxeter honeycombs) in hyperbolic 3-space $\mathbb{H}^3$. Centers of horoballs are required to lie at vertices of the regular polyhedral cells constituting the tiling. We allow horoballs of different types at the various vertices. Our results are derived through a generalization of the projective methodology for hyperbolic spaces. The main result...

Source: http://arxiv.org/abs/1007.0722v2

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Jul 20, 2013
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Jul 20, 2013
by
Thomas Koberda

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Consider the mapping class group $\Mod_{g,p}$ of a surface $\Sigma_{g,p}$ of genus $g$ with $p$ punctures, and a finite collection $\{f_1,...,f_k\}$ of mapping classes, each of which is either a Dehn twist about a simple closed curve or a pseudo-Anosov homeomorphism supported on a connected subsurface. In this paper we prove that for all sufficiently large $N$, the mapping classes $\{f_1^N,...,f_k^N\}$ generate a right-angled Artin group. The right-angled Artin group which they generate can be...

Source: http://arxiv.org/abs/1007.1118v4

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Jul 20, 2013
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Jul 20, 2013
by
Holger Dette; Jan Nagel

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In this paper we define distributions on moment spaces corresponding to measures on the real line with an unbounded support. We identify these distributions as limiting distributions of random moment vectors defined on compact moment spaces and as distributions corresponding to random spectral measures associated with the Jacobi, Laguerre and Hermite ensemble from random matrix theory. For random vectors on the unbounded moment spaces we prove a central limit theorem where the centering vectors...

Source: http://arxiv.org/abs/1007.3369v2

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Jul 20, 2013
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Jul 20, 2013
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Pranav Dandekar; Ashish Goel; Ramesh Govindan; Ian Post

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Credit networks represent a way of modeling trust between entities in a network. Nodes in the network print their own currency and trust each other for a certain amount of each other's currency. This allows the network to serve as a decentralized payment infrastructure---arbitrary payments can be routed through the network by passing IOUs between trusting nodes in their respective currencies---and obviates the need for a common currency. Nodes can repeatedly transact with each other and pay for...

Source: http://arxiv.org/abs/1007.0515v3

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Jul 20, 2013
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Jul 20, 2013
by
Linda M. Carpenter

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In an attempt to maximize General Gauge Mediated parameter space, I propose simple models in which gauginos and scalars are generated from disconnected mechanisms. In my models Dirac gauginos are generated through the supersoft mechanism, while independent R-symmetric scalar masses are generated through operators involving non-zero messenger supertrace. I propose several new methods for generating negative messenger supertraces which result in viable positive mass squareds for MSSM scalars. The...

Source: http://arxiv.org/abs/1007.0017v2

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Jul 20, 2013
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Jul 20, 2013
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E. D. Mun; S. Jia; S. L. Bud'ko; P. C. Canfield

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The thermoelectric power, $S(T)$, of the heavy fermions YbT$_{2}$Zn$_{20}$ ($T$ = Fe, Ru, Os, Ir, Rh, and Co) has been measured to characterize their strong electronic correlations. A large, negative, local minimum in $S(T)$ with approximately -70 $\mu$V/K is found for all compounds. From the observed local minimum, the energy scales associated with both the Kondo temperature and the crystalline electric field splitting are deduced and compared to previous specific heat measurements. At low...

Source: http://arxiv.org/abs/1007.4244v2

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Jul 20, 2013
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Jul 20, 2013
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D. Dikranjan; Gábor Lukács

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In this paper, we describe the relationship between the quasi-component q(G) of a (perfectly) minimal pseudocompact abelian group G and the quasi-component q(\widetilde G) of its completion. Specifically, we characterize the pairs (C,A) of compact connected abelian groups C and subgroups A such that A \cong q(G) and C \cong q(\widetilde G). As a consequence, we show that for every positive integer n or n=\omega, there exist plenty of abelian pseudocompact perfectly minimal n-dimensional groups...

Source: http://arxiv.org/abs/1007.4285v3

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Jul 20, 2013
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Jul 20, 2013
by
Leonel Robert

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A classification result is obtained for the C*-algebras that are (stably isomorphic to) inductive limits of 1-dimensional noncommutative CW complexes with trivial $K_1$-group. The classifying functor Cu is defined in terms of the Cuntz semigroup of the unitization of the algebra. For the simple C*-algebras covered by the classification, Cu reduces to the ordered $K_0$-group, the cone of traces, and the pairing between them. As an application of the classification, it is shown that the crossed...

Source: http://arxiv.org/abs/1007.1964v3

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Jul 20, 2013
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Jul 20, 2013
by
Josef Dick

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We study a random sampling technique to approximate integrals $\int_{[0,1]^s}f(\mathbf{x})\,\mathrm{d}\mathbf{x}$ by averaging the function at some sampling points. We focus on cases where the integrand is smooth, which is a problem which occurs in statistics. The convergence rate of the approximation error depends on the smoothness of the function $f$ and the sampling technique. For instance, Monte Carlo (MC) sampling yields a convergence of the root mean square error (RMSE) of order...

Source: http://arxiv.org/abs/1007.0842v4

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Jul 20, 2013
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Jul 20, 2013
by
Lorenzo Di Biagio; Elisa Postinghel

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A result by Macaulay states that an Artinian graded Gorenstein ring R of socle dimension one and socle degree b can be realized as the apolar ring of a homogeneous polynomial f of degree b. If R is the Jacobian ring of a smooth hypersurface g=0, then b is just equal to the degree of the Hessian polynomial of g. In this paper we investigate the relationship between f and the Hessian polynomial of g.

Source: http://arxiv.org/abs/1007.4891v2

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Jul 20, 2013
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Jul 20, 2013
by
Alessandra Faggionato; Fabio Martinelli; Cyril Roberto; Cristina Toninelli

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Motivated by several models introduced in the physics literature to study the nonequilibrium coarsening dynamics of one-dimensional systems, we consider a large class of "hierarchical coalescence processes" (HCP). An HCP consists of an infinite sequence of coalescence processes ${\xi^{(n)}(\cdot)}_{n\ge1}$: each process occurs in a different "epoch" (indexed by $n$) and evolves for an infinite time, while the evolution in subsequent epochs are linked in such a way that the...

Source: http://arxiv.org/abs/1007.0109v2

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Jul 20, 2013
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Jul 20, 2013
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Sophie Laruelle; Gilles Pagès

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The aim of the paper is to establish a convergence theorem for multi-dimensional stochastic approximation when the "innovations" satisfy some "light" averaging properties in the presence of a pathwise Lyapunov function. These averaging assumptions allow us to unify apparently remote frameworks where the innovations are simulated (possibly deterministic like in Quasi-Monte Carlo simulation) or exogenous (like market data) with ergodic properties. We propose several fields of...

Source: http://arxiv.org/abs/1007.3578v4

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118

Jul 20, 2013
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Jul 20, 2013
by
A. J. Cuesta; T. E. Jeltema; F. Zandanel; S. Profumo; F. Prada; G. Yepes; A. Klypin; Y. Hoffman; S. Gottloeber; J. Primack; M. A. Sanchez-Conde; C. Pfrommer

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We present all-sky simulated Fermi maps of gamma-rays from dark matter decay and annihilation in the Local Universe. The dark matter distribution is obtained from a constrained cosmological simulation of the neighboring large-scale structure provided by the CLUES project. The dark matter fields of density and density squared are then taken as an input for the Fermi observation simulation tool to predict the gamma-ray photon counts that Fermi would detect in 5 years of all-sky survey for given...

Source: http://arxiv.org/abs/1007.3469v3

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Jul 20, 2013
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Jul 20, 2013
by
Sahazada Aziz; Buddhadeb Ghosh

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We study electroweak baryogenesis within the framework of the littlest Higgs model with T parity. This model has shown characteristics of a strong first-order electroweak phase transition, which is conducive to baryogenesis in the early Universe. In the T parity symmetric theory, there are two gauge sectors, viz., the T-even and the T-odd ones. We observe that the effect of the T-parity symmetric interactions between the T-odd and the T-even gauge bosons on gauge-higgs energy functional is...

Source: http://arxiv.org/abs/1007.0485v4

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Jul 20, 2013
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Jul 20, 2013
by
Ioannis Souldatos

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This is part I of a study on cardinals that are characterizable by Scott sentences. Building on [3], [6] and [1] we study which cardinals are characterizable by a Scott sentence $\phi$, in the sense that $\phi$ characterizes $\kappa$, if $\phi$ has a model of size $\kappa$, but no models of size $\kappa^+$. We show that the set of cardinals that are characterized by a Scott sentence is closed under successors, countable unions and countable products (cf. theorems 2.3, 3.4, and corollary 3.6)....

Source: http://arxiv.org/abs/1007.2426v3

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Jul 20, 2013
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Jul 20, 2013
by
Serge Cantat; Stéphane Lamy

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Let k be an algebraically closed field. We show that the Cremona group of all birational transformations of the projective plane P^2 over k is not a simple group. The strategy makes use of hyperbolic geometry, geometric group theory, and algebraic geometry to produce elements in the Cremona group that generate non trivial normal subgroups.

Source: http://arxiv.org/abs/1007.0895v2

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Jul 20, 2013
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Jul 20, 2013
by
Jean-Pierre Fouque; Sebastian Jaimungal; Matthew Lorig

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Using spectral decomposition techniques and singular perturbation theory, we develop a systematic method to approximate the prices of a variety of options in a fast mean-reverting stochastic volatility setting. Four examples are provided in order to demonstrate the versatility of our method. These include: European options, up-and-out options, double-barrier knock-out options, and options which pay a rebate upon hitting a boundary. For European options, our method is shown to produce option...

Source: http://arxiv.org/abs/1007.4361v2

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91

Jul 20, 2013
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Jul 20, 2013
by
Yossi Azar; Iftah Gamzu

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We study the problem of maximizing a monotone submodular set function subject to linear packing constraints. An instance of this problem consists of a matrix $A \in [0,1]^{m \times n}$, a vector $b \in [1,\infty)^m$, and a monotone submodular set function $f: 2^{[n]} \rightarrow \bbR_+$. The objective is to find a set $S$ that maximizes $f(S)$ subject to $A x_{S} \leq b$, where $x_S$ stands for the characteristic vector of the set $S$. A well-studied special case of this problem is when $f$ is...

Source: http://arxiv.org/abs/1007.3604v2

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74

Jul 20, 2013
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Jul 20, 2013
by
Wojciech Domitrz; P. de M. Rios

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We define the Global Centre Symmetry set (GCS) of a smooth closed m-dimensional submanifold M of R^n, $n \leq 2m$, which is an affinely invariant generalization of the centre of a k-sphere in R^{k+1}. The GCS includes both the centre symmetry set defined by Janeczko and the Wigner caustic defined by Berry. We develop a new method for studying generic singularities of the GCS which is suited to the case when M is lagrangian in R^{2m} with canonical symplectic form. The definition of the GCS,...

Source: http://arxiv.org/abs/1007.1939v4

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Jul 20, 2013
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Jul 20, 2013
by
Jarosław Buczyński; Adam Ginensky; J. M. Landsberg

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We address special cases of a question of Eisenbud on the ideals of secant varieties of Veronese re-embeddings of arbitrary varieties. Eisenbud's question generalizes a conjecture of Eisenbud, Koh and Stillman (EKS) for curves. We prove that set-theoretic equations of small secant varieties to a high degree Veronese re-embedding of a smooth variety are determined by equations of the ambient Veronese variety and linear equations. However this is false for singular varieties, and we give explicit...

Source: http://arxiv.org/abs/1007.0192v4

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Jul 20, 2013
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Jul 20, 2013
by
Henrik Seppänen

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Let $\mathscr{L} \rightarrow X$ be an ample line bundle over a nonsingular complex projective variety $X$. We construct an admissable flag $X_0 \subseteq X_1 \subseteq...\subseteq X_n=X$ of subvarieties for which the associated Okounkov body for $\mathscr{L}$ is a rational polytope.

Source: http://arxiv.org/abs/1007.1915v3

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Jul 20, 2013
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Jul 20, 2013
by
Kazuhiko Yamaki

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In this paper, we formulate the geometric Bogomolov conjecture for abelian varieties, and give some partial answers to it. In fact, we insist in a main theorem that under some degeneracy condition, a closed subvariety of an abelian variety does not have a dense subset of small points if it is a non-special subvariety. The key of the proof is the study of the minimal dimension of the components of a canonical measure on the tropicalization of the closed subvariety. Then we can apply the tropical...

Source: http://arxiv.org/abs/1007.1081v5

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122

Jul 20, 2013
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Jul 20, 2013
by
Yiyuan She

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Supervised linear feature extraction can be achieved by fitting a reduced rank multivariate model. This paper studies rank penalized and rank constrained vector generalized linear models. From the perspective of thresholding rules, we build a framework for fitting singular value penalized models and use it for feature extraction. Through solving the rank constraint form of the problem, we propose progressive feature space reduction for fast computation in high dimensions with little performance...

Source: http://arxiv.org/abs/1007.3098v3

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Jul 20, 2013
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Jul 20, 2013
by
Reza Mirghaderi; Andrea Goldsmith; Tsachy Weissman

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We investigate the achievable error probability in communication over an AWGN discrete time memoryless channel with noiseless delay-less rate-limited feedback. For the case where the feedback rate R_FB is lower than the data rate R transmitted over the forward channel, we show that the decay of the probability of error is at most exponential in blocklength, and obtain an upper bound for increase in the error exponent due to feedback. Furthermore, we show that the use of feedback in this case...

Source: http://arxiv.org/abs/1007.1986v3

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164

Jul 20, 2013
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Jul 20, 2013
by
T. Fülöp; P. Ván

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Kinematic quantities for finite elastic and plastic deformations are defined via an approach that does not rely on auxiliary elements like reference frame and reference configuration, and that gives account of the inertial-noninertial aspects explicitly. These features are achieved by working on Galilean spacetime directly. The quantity expressing elastic deformations is introduced according to its expected role: to measure how different the current metric is from the relaxed/stressless metric....

Source: http://arxiv.org/abs/1007.2892v5

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Jul 20, 2013
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Jul 20, 2013
by
Adrian Ioana; Sorin Popa; Stefaan Vaes

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We prove that for any group G in a fairly large class of generalized wreath product groups, the associated von Neumann algebra L(G) completely "remembers" the group G. More precisely, if L(G) is isomorphic to the von Neumann algebra L(\Lambda) of an arbitrary countable group \Lambda, then \Lambda\ must be isomorphic to G. This represents the first superrigidity result pertaining to group von Neumann algebras.

Source: http://arxiv.org/abs/1007.1412v3

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Jul 20, 2013
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Jul 20, 2013
by
Carlo Morosi; Livio Pizzocchero

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We consider the incompressible Euler or Navier-Stokes (NS) equations on a d-dimensional torus T^d; the quadratic term in these equations arises from the bilinear map sending two velocity fields v, w : T^d -> R^d into v . D w, and also involves the Leray projection L onto the space of divergence free vector fields. We derive upper and lower bounds for the constants in some inequalities related to the above quadratic term; these bounds hold, in particular, for the sharp constants K_{n d} = K_n...

Source: http://arxiv.org/abs/1007.4412v3

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Jul 20, 2013
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Jul 20, 2013
by
Baptiste Auguié; Xesús M. Bendaña; William L. Barnes; F. Javier García de Abajo

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The optical properties of periodic arrays of plasmonic nanoantennas are strongly affected by coherent multiple scattering in the plane of the array, which leads to sharp spectral resonances in both transmission and reflection when the wavelength is commensurate with the period. We demonstrate that the presence of a substrate (i.e., an asymmetric refractive-index environment) can inhibit long-range coupling between the particles and suppress lattice resonances, in agreement with recent...

Source: http://arxiv.org/abs/1007.4428v3

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Jul 20, 2013
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Jul 20, 2013
by
Michael Thomas

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For decision problems P defined over Boolean circuits from a restricted set of gates, we have that P(B) AC0 many-one reduces to P(B') for all finite sets B and B' of gates such that all gates from B can be computed by circuits over gates from B'. In this paper, we show that a weaker version of this statement holds for decision problems defined over Boolean formulae, namely that P(B) NC2 many-one reduces to P(B' union {and,or}) and that P(B) NC2 many-one reduces to P(B' union {false,true}), for...

Source: http://arxiv.org/abs/1007.2924v3

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Jul 20, 2013
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Jul 20, 2013
by
Nils Waterstraat

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We give a short proof of the Morse index theorem for geodesics in semi-Riemannian manifolds by using K-theory. This makes the Morse index theorem reminiscent of the Atiyah-Singer index theorem for families of selfadjoint elliptic operators.

Source: http://arxiv.org/abs/1007.1190v3

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Jul 20, 2013
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Jul 20, 2013
by
Ismaël Bailleul; Jacques Franchi

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Some general Lorentz covariant operators, associated to the so-called \Theta (or \Xi)-relativistic diffusions and making sense in any Lorentzian manifold, have been introduced by Franchi and Le Jan [Comm. Pure Appl. Math. 60 (2007) 187-251], Franchi and Le Jan [Curvature diffusions in general relativity (2010). Unpublished manuscript]. Only a few examples have been studied so far. We provide in this work some nonexplosion criteria for these diffusions, which can be used in generic cases.

Source: http://arxiv.org/abs/1007.1893v3

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Jul 20, 2013
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Jul 20, 2013
by
Tomoyuki Yamakami

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Constraint satisfaction problems (or CSPs) have been extensively studied in, for instance, artificial intelligence, database theory, graph theory, and statistical physics. From a practical viewpoint, it is beneficial to approximately solve those CSPs. When one tries to approximate the total number of truth assignments that satisfy all Boolean-valued constraints for (unweighted) Boolean CSPs, there is a known trichotomy theorem by which all such counting problems are neatly classified into...

Source: http://arxiv.org/abs/1007.0391v4

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Jul 20, 2013
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Jul 20, 2013
by
Wicher Bergsma; Angelos Dassios

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The most popular ways to test for independence of two ordinal random variables are by means of Kendall's tau and Spearman's rho. However, such tests are not consistent, only having power for alternatives with `monotonic' association. In this paper we introduce a natural extension of Kendall's tau, called $\tau^*$, which is nonnegative and zero if and only if independence holds, thus leading to a consistent independence test. Furthermore, normalization gives a rank correlation which can be used...

Source: http://arxiv.org/abs/1007.4259v5

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42

Jul 20, 2013
07/13

Jul 20, 2013
by
H. T. Ng; Franco Nori

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We propose an alternative method to factorize an integer by using three harmonic oscillators. These oscillators are coupled together via specific Kerr nonlinear interactions. This method can be applied even if two harmonic oscillators are prepared in mixed states. As simple examples, we show how to factorize N=15 and 35 using this approach. The effect of dissipation of the harmonic oscillators on the performance of this method is studied. We also study the realization of nonlinear interactions...

Source: http://arxiv.org/abs/1007.4338v2

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118

Jul 20, 2013
07/13

Jul 20, 2013
by
Min Sha; Linsheng Yin

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We call a (q-1)-th Kummer extension of a cyclotomic function field a quasi-cyclotomic function field if it is Galois, but non-abelian, over the rational function field with the constant field of q elements. In this paper, we determine the structure of the Galois groups of a kind of quasi-cyclotomic function fields over the base field. We also give the genus formulae of them.

Source: http://arxiv.org/abs/1007.1729v2

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96

Jul 20, 2013
07/13

Jul 20, 2013
by
Vikram Krishnamurthy

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We consider how local and global decision policies interact in stopping time problems such as quickest time change detection. Individual agents make myopic local decisions via social learning, that is, each agent records a private observation of a noisy underlying state process, selfishly optimizes its local utility and then broadcasts its local decision. Given these local decisions, how can a global decision maker achieve quickest time change detection when the underlying state changes...

Source: http://arxiv.org/abs/1007.0571v3

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Jul 20, 2013
07/13

Jul 20, 2013
by
Régis Monneau; Stefania Patrizi

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This paper is concerned with a result of homogenization of an integro-differential equation describing dislocation dynamics. Our model involves both an anisotropic L\'{e}vy operator of order 1 and a potential depending periodically on $u/\ep$. The limit equation is a non-local Hamilton-Jacobi equation, which is an effective plastic law for densities of dislocations moving in a single slip plane.

Source: http://arxiv.org/abs/1007.2915v2

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86

Jul 20, 2013
07/13

Jul 20, 2013
by
Omid Amini

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Given a divisor $D$ on a tropical curve $\Gamma$, we show that reduced divisors define an integral affine map from the tropical curve to the complete linear system $|D|$. This is done by providing an explicit description of the behavior of reduced divisors under infinitesimal modifications of the base point. We consider the cases where the reduced-divisor map defines an embedding of the curve into the linear system, and in this way, classify all the tropical curves with a very ample canonical...

Source: http://arxiv.org/abs/1007.5364v2